chapter 9 Flashcards
the gravitationally bound outer gaseous layer that envelopes and surrounds a planet, star & moon
atmosphere
young planets captured some of the surrounding hydrogen & helium that filled the protoplanetary disk
atmosphere phase 1
sunlight heated the atmospheres and rapid thermal motion of light atoms and molecules caused the primary atmospheres to escape
atmosphere phase 2
volcanoes & comets release gas, water, and other molecules to form a secondary atmosphere
atmosphere phase 3
more massive planets retain an atmosphere while smaller objects cannot
atmosphere phase 4
11.2 km/s
escape velocity of earth
collision of fast-moving ions with a surface or atmosphere that causes the loss of material from the surface/atmosphere
sputtering
the acceleration (downward) due to gravity measured at the surface of a planet/star
surface gravity
the solar heating of air in an enclosed space, resulting primarily from the inability of the hot air to escape
atmospheric greenhouse effect
atmospheric gasses–such as carbon dioxide, water vapor, methane, nitrous oxide, and halogens– that are transparent to visible radiation but absorb sunlight/heat
greenhouse gases
4/5 nitrogen and 1/5 oxygen
earth’s atmosphere
formed when UV light from the sun breaks molecular oxygen into its individual atoms, then recombines to form a new molecule
ozone
the atmospheric layer immediately above the troposphere; between 10-50 km in altitude
stratosphere
- materials that participate in accelerating chemical reactions, but are not modified in the process
- ex: halogens
catalyst
5 x 10^8 kg
mass of earth’s atmosphere
- the lowest layer of atmosphere that humans live and breathe in
- contains 90% of the atmospheric mass
troposphere
the amount of water vapor held by a volume of air at a given temp.
relative humidity
the boundary between the troposphere and the stratosphere; altitude of 50-90 km
tropopause
- layer of atmosphere greater than 90 km and 600 km
- warmest layer
thermosphere
a layer high in the atmosphere which most atoms are ionized by solar radiation
ionosphere
a large region filled with electrons, protons, and other charged particles from the sun that have been captured by earth’s magnetic field
magnetosphere
- a toroidal ring of high-energy particles that surround a planet
- glowing rings cause auroras
radiation belt
the cycle of air moving between the equator & the poles of a planet
hadley circulation
the east-west component of a wind
zonal winds
